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%I #4 Jan 20 2018 09:08:31
%S 1,12,10,50,148,493,2093,8047,31951,128472,511830,2047349,8191875,
%T 32754509,131023111,524086312,2096237838,8384859457,33538726179,
%U 134151944073,536597656559,2146347416764,8585218405150,34340195856617
%N Number of nX3 0..1 arrays with every element equal to 0, 2, 3, 4 or 7 king-move adjacent elements, with upper left element zero.
%C Column 3 of A298508.
%H R. H. Hardin, <a href="/A298503/b298503.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 5*a(n-1) -4*a(n-2) +5*a(n-3) -25*a(n-4) +24*a(n-5) -23*a(n-6) +21*a(n-7) +44*a(n-8) -69*a(n-9) -5*a(n-10) +48*a(n-11) -26*a(n-12) +22*a(n-13) -10*a(n-14) -8*a(n-15) +4*a(n-16) for n>18
%e Some solutions for n=7
%e ..0..1..0. .0..1..1. .0..0..0. .0..1..0. .0..1..0. .0..1..1. .0..1..0
%e ..0..0..0. .1..1..0. .0..1..0. .0..0..0. .0..0..0. .0..0..1. .0..0..0
%e ..0..0..0. .0..0..0. .1..0..1. .0..0..0. .0..0..0. .0..1..1. .0..0..0
%e ..0..1..0. .1..0..1. .1..1..1. .0..1..0. .0..1..0. .0..1..0. .0..1..0
%e ..0..0..0. .1..1..1. .1..1..1. .0..1..1. .0..1..1. .0..0..0. .1..1..1
%e ..1..1..1. .1..1..1. .1..0..1. .1..0..0. .0..0..1. .0..0..0. .0..0..0
%e ..0..1..0. .1..0..1. .0..0..0. .1..1..0. .0..1..1. .0..1..0. .1..0..0
%Y Cf. A298508.
%K nonn
%O 1,2
%A _R. H. Hardin_, Jan 20 2018